1. Field
The subject matter disclosed herein relates to electronic devices, and more particularly to methods, apparatuses and articles of manufacture for use in electronic devices that may selectively operate in different power modes.
2. Information
The Global Positioning System (GPS) and other like satellite positioning systems (SPSs) have enabled navigation services for devices in outdoor environments. Since some satellite signals may not be reliably received and/or acquired in an indoor environment, different techniques may be employed to enable position location and/or other like navigation services. In an indoor application, for example, certain devices may obtain a position fix by measuring ranges to terrestrial wireless access points (e.g., IEEE Std. 802.11 access points, etc.) that are positioned at known locations. Such ranges may be measured, for example, by obtaining a MAC ID address from signals received from such access points and measuring one or more characteristics of the received signals such as, for example, a signal strength, a round trip time (RTT) delay, a time of flight (TOF), just to name a few examples. In addition to SPSs and indoor positioning systems, existing wireless carrier infrastructures may enable observed time difference of arrival (OTDOA) and/or advanced forward link trilateration (AFLT) techniques for estimating locations of applicable devices. For example, with knowledge of the locations of neighboring base station transmitters and time-reference data, a device may estimate a range to such base station transmitters based upon an observed signal propagation delay (e.g., by comparing a phase value of an acquired signal to a time reference).